Method for producing a multiple filamented cartridge lamp

ABSTRACT

A method for producing multiple filamented cartridge lamps is disclosed. The multiple filaments are connected together on the external ends of a cartridge lamp by linking members and then the ends of the lamp are press sealed. Thereafter, a linking member is separated externally on at least one end to form separate terminals for each filament whereby each filament can have a separate source of energy.

United States Patent 1191 C urtis 1 1 Feb. 12, 1974 METHOD FOR PRODUCINGA MULTIPLE FILAMENTED CARTRIDGE LAMP [75] Inventor: Lorin W. Curtis, SunCity, Calif.

[73] Assignee: Wagner Electric Corporation,

Newark, NJ.

22 Filed: Mar. 24, 1972 [2]] Appl. No.: 237,847

Ayres et al 316/17 3,265,923 8/1966 Peziosi et al 313/318 3,286,11811/1966 Vause et al. 313/318 3,496,403 2/1970 Palermo et al 313/222Primary Examiner-Roy Lake Assistant Examiner-J. W. Davie Attorney,Agent, or Firm Eyre, Mann & Lucas 1 57] ABSTRACT A method for producingmultiple filamented cartridge lamps is disclosed. The multiple filamentsare con nected together on the external ends of a cartridge lamp bylinking members and then the ends of. the lamp are press sealed.Thereafter, a linking member is separated externally on at least one endto form separate terminals for each filament whereby each filament canhave a separate source of energy.

6 Claims, 5 Drawing Figures 1 METHOD FOR PRODUCING A MULTIPLE FILAMENTEDCARTRIDGE LAIVH The present invention is a new and useful method forproducing a multiple filamented cartridge-type lamp and is especiallyuseful for producing a two filamented lamp. The two filaments are joinedtogether by a U shaped linking member at each end whereby the twofilaments will be held in spaced relation to each other during thesubsequent forming of the lamp. The joined filaments are placed insidethe lamp with the linking members extending'exter'nal thereto. The lampis then exhausted by the flush method and an instantaneous press seal isapplied to each end of the lamp. If desired, one end of the lamp can bepress sealed before flushing and the other after flushing. Thereafter,the linking member is separated on at least one end of the lamp,

whereby each filament may be operated separately with a common ground.Alternatively, the linking members may be separated at both ends andeach filament can be used in a completely separate circuit. The lampshave particular application in the automotive industry as combinationstop and tail lights or combination tail light and turn signal light.

The lamps formed by the present invention have considerable advantageover the prior art since the filaments are linked together during theformation of the lamp and it is not necessary to hold them separately bythe application of external holding means. This is a simple andcomparatively low cost method of making multiple filamented lamps.

These and other aspects of the present invention may be more fullyunderstood with reference to the drawings in which:

FIG. 1 shows a multiple filament assembly formed in accordance with thepresent invention before insertion into the lamp case;

FIG. 2 shows a two filament assembly press sealed in a glass bulb;

FIG. 3 shows the two filament assembly in the lamp of FIG. 2 with oneset of terminal posts and a common ground;

FIG. 4 shows the two filament assembly in the lamp of FIG. 2 with twosets of terminal posts each independent; and

FIG. 5 shows the lamp assembly of FIG. 3 with a cap on the common endthereof.

In FIG. 1 is shown three filaments 10, 11 and 12 linked in accordancewith the present invention before insertion into the lamp case, usuallya glass bulb. The filaments 10, 11 and 12 have lead-in wires 14, l5, 16,17, and 18, respectively and the filaments are suitably joined to thelead-in wires by folding over tabs on the lead-in wires as shown. Thelead-in wires 14, 16, 18 are joined at one end suitably by welding tolinking member 22 and lead-in wires 15, 17, 20 are joined at the otherend by linkingmember 23. The linking members 22 and 24 are preferablymade of either nickel or Kovar. Kovar isa Westinghouse tradename for asealing alloy consisting of iron, nickel and chromium. The lead-in wiresl4, 15, 16, 17,18 and 20 are suitably made of dumet or Kovar which aresealing alloys. Dumet is a generic name for a sealing metal for softglass consisting of an alloy of nickel and iron usually covered by asleeve of copper which in turn is covered with a nickel plate or aborated surface and is available from General Electric, Westinghouse,Sylvania and Texas Instruments. The particular sealing alloy isdependent upon the material used for the envelop; usually dumet whensoda lime glass is used and Kovar when heat resistant glass is used suchas Corning 7052 or 7056. The filaments 1 l, 10 and 12 are suitably madeof tungsten.

In FIG. 2 there is shown a two filament assembly similar to the threefilament assembly of FIG. 1 encased within a glass envelop 26. Thelinking members 24 and 25 are similar to linking members 22 and 23except that provision is made for connecting only two filaments. Thefilaments shown in FIG. 2 are connected to the linking members in thesame manner shown and described for FIG. 1. The envelop has been heatedat its ends and press sealed in standard manner at 28 and 30. Beforesealing at the second end, the lamp was exhausted by the flush method,preferably with nitrogen or argon or any other suitable inert gas. Inthe preferred embodiment of the invention soda lime glass is used forthe bulb, the sealing alloy is nickel plated dumet and the linkingmember is nickel.

After the two filament assembly has been sealed in the bulb, the linkingmember 24 is separated as shown in FIG. 3 so that separate terminals'32and 34 are provided at one end of the bulb. With this construction, thelinking member 25 can serve as a ground and sepa. rate signals can befed to terminals 32 and 34. An alternative form of construction is shownin FIG. 4 wherein both linking members 24 and 25 have been severed,forming terminals 32, 34 and 36, 38. With this construction, thefilament with terminals 34, 36 can have a completely separate supplyfrom the filament with terminals 32, 38.

In the embodiment of FIG. 3, the end 40 of the lamp may be provided witha standard metal cap 42 as shown in FIG. 5; While this is desirable, itis not necessary.

It will be understood that the claims are intended to cover all changesand modifications of the preferred embodiments of the invention, hereinchosen for the purpose of illustration, which do not constitutedepartures from the spirit and scope of the invention.

I claim:

1. A process for manufacturing multiple filamented lamps wherein atleast one filament can be operated independently of the otherscomprising:

a. forming a-filament assembly comprising a plurality of spacedfilaments joined at each end to separate lead-in conductors which inturn are joined to opposed linking members by i. affixing lead-inconductors to opposed ends of each filament,

ii. connecting the lead-in conductors on one end of each filament-tospaced legs of a linking member, and

iii. connecting the lead-in conductors on the other end of each filamentto spaced legs of a second linking member;

b. inserting the filament assembly into a lamp case to form a lampassembly;

c. flushing the lamp assembly and press sealing the ends of the lampcase to form a sealed lamp assembly enclosing at least a portion of eachof the legs of the linking members and at least a portion of each of theconductors, in the press seal with at least a portion of each of thelinking members being external of the pressseal and the lamp case and atleast a portion of each of the conductors being enclosed within the lampcase inward of the press seal and each of the filaments being entirelyenclosed within the lamp case inward of the press seal; and

d. severing a linking member at at least one point on at least one endof the sealed lamp assembly external of the lamp case to separate atleast two legs of the linking member whereby at least one portion of thesevered linking member may be used for operation of at least onefilament independent of the operation of the other filaments.

2. The process of claim 1 wherein the linking members are severed atboth ends of the sealed lamp assembly to provide separate terminals foreach filament.

3, The process of claim 1 wherein only one of the linking members issevered and further including the step of placing a cap on the end ofthe lamp with the non-severed linking member.

4. The process of claim 1 wherein one end of the lamp case is presssealed before flushing.

5. The process of claim 1 wherein flushing is begun before either end ofthe lamp case has been press sealed.

6. The process of claim 1 wherein flushing is begun before press sealingof either end, one end of the lamp is press sealed, and flushing iscontinued until the instant of the seal of the other end.

1. A process for manufacturing multiple filamented lamps wherein atleast one filament can be operated independently of the otherscomprising: a. forming a filament assembly comprising a plurality ofspaced filaments joined at each end to separate lead-in conductors whichin turn are joined to opposed linking members by i. affixing lead-inconductors to opposed ends of each filament, ii. connecting the lead-inconductors on one end of each filament to spaced legs of a linkingmember, and iii. connecting the lead-in conductors on the other end ofeach filament to spaced legs of a second linking member; b. insertingthe filament assembly into a lamp case to form a lamp assembly; c.flushing the lamp assembly and press sealing the ends of the lamp caseto form a sealed lamp assembly enclosing at least a portion of each ofthe legs of the linking members and at least a portion of each of theconductors in the press seal with at least a portion of each of thelinking members being external of the press seal and the lamp case andat least a portion of each of the conductors being enclosed within thelamp case inward of the press seal and each of the filaments beingentirely enclosed within the lamp case inward of the press seal; and d.severing a linking member at at least one point on at least one end ofthe sealed lamp assembly external of the lamp case to separate at leasttwo legs of the linking member whereby at least one portion of thesevered linking member may be used for operation of at least onefilament independent of the operation of the other filaments.
 2. Theprocess of claim 1 wherein the linking members are severed at both endsof the sealed lamp assembly to provide separate terminals for eachfilament.
 3. The process of claim 1 wherein only one of the linkingmembers is severed and further including the step of placing a cap onthe end of the lamp with the non-severed linking member.
 4. The processof claim 1 wherein one end of the lamp case is press sealed beforeflushing.
 5. The process of claim 1 wherein flushing is begun beforeeither end of the lamp case has been press sealed.
 6. The process ofclaim 1 wherein flushing is begun before press sealing of either end,one end of the lamp is press sealed, and flushing is continued until theinstant of the seal of the other end.